1. Field of the Invention
This invention relates to an external wall structure, and in particular, to an external wall structure of a joint portion between upper and lower siding boards of a longitudinal joint type.
2. Description of the Related Arts
In the siding work for the external wall of building, a plurality of longitudinal joint type siding boards are employed in such a manner that they are installed side by side and coupled with each other in the horizontal direction as well as in the vertical direction. For example, the coupling of these longitudinal joint type siding boards which are installed side by side in the horizontal direction is performed through a shiplap joint between the opposite sides of these boards, while the coupling of upper and lower longitudinal joint type siding boards through their longitudinal sides is performed using a horizontally elongated draining member which is designed to be interposed between these siding boards.
FIG. 5 shows one example of such a coupling method, wherein a horizontally elongated draining member 20 is secured by means of nail 5 to a horizontal furring strip 10 of a building wall, and then an upper siding board 1 and a lower siding board 1 are coupled with each other with this draining member 20 being interposed therebetween. In this example, as shown in FIG. 6 illustrating a perspective view thereof, the draining member 20 is constituted by a horizontally elongated substrate 21, and a couple of board-receiving portions 24 and 25 protruded externally from the substrate 21 and provided with an upward holder portion 22 and a downward holder portion 23, respectively, so that a lower end portion 3 of the upper siding board 1 is enabled to be fitted in the upward holder portion 22, while an upper end portion 3 of the lower siding board 1 is enabled to be fitted in the downward holder portion 23. Further, the upper board-receiving portion 24 of draining member 20 is provided with a elliptical drain hole 26 to thereby allow rain water running down through the siding board 1 to be discharged via this drain hole 26 out of the upper board-receiving portion 24. By the way, this draining member 20 is provided with a plurality of spacer ribs 27 which are protruded at predetermined intervals from the rear surface of the substrate 21, thereby enabling a gap to be formed for ventilation on the rear side of substrate 21 as the draining member 20 is secured to the horizontal furring strip 10 (see Japanese Patent Unexamined Publication 2000-160804, for instance).
According to this external wall structure wherein a couple of siding boards are coupled with each other through their longitudinal sides by making use of a horizontally elongated draining member which is attached in advance to a building wall and designed to be interposed between these siding boards as shown in FIG. 5, a portion of the draining member (the board-receiving portions 24 and 25, in this example) is permitted to expose to the outside. Although there is not any particular inconvenience in itself as an external wall structure, it is occasionally desired that the aforementioned exposed portion of draining member is also covered with a decorative end rail for enhancing the design of the external wall.
This invention has been accomplished with a view to response to such a demand, and therefore, an object of the present invention is to provide an external wall structure, which makes it possible to cover a portion of draining member which is exposed to the outside with a desired decorative plate through a simple supplementary work on the occasion of installing siding boards or even after the installation of siding boards.
With a view to realize the aforementioned object, this invention provides an external wall structure, which comprises a horizontally elongated draining member which is secured to a building wall, and a couple of upper and lower siding boards which are coupled with each other with said draining member being interposed therebetween; wherein a horizontally elongated decorative plate is mounted via a fixture on a joint portion between said couple of upper and lower siding boards, thereby covering said joint portion.
As for the specific configuration of the draining member to be employed in this invention, there is not any particular limitation as long as it is capable of draining water as it is interposed between a couple of upper and lower siding boards. For example, the draining member may be such as shown in FIGS. 5 and 6 wherein the draining member is provided with a couple of holder portions for enabling a lower end portion of the upper siding board and an upper end portion of the lower siding board to be fitted in the holder portions, respectively. Alternatively, the draining member may be such that it comprises a slanted plate portion having a pent roof configuration so as to cover an upper end portion of lower siding board, and a perpendicular draining plate portion.
In the siding work, a horizontally elongated draining member is secured by means of nail, etc. to a horizontal furring strip of building wall, and at the same time, siding boards are coupled with each other in the longitudinal direction thereof as well as in the elevational direction thereof. During or subsequent to this siding work, a required number of fixtures are attached at predetermined intervals to the draining member by any suitable means. Thereafter, by taking advantage of these fixtures attached in this manner, a horizontally elongated decorative plate is mounted on the joint portion between a couple of upper and lower siding boards (i.e. a portion of draining member which is exposed to the outside ), thereby covering the joint portion. Preferably, the fixture is provided at the upper and lower ends thereof with a horizontally extending locking end, while the decorative plate is provided at the upper and lower edges thereof with a hook which is designed to be engaged with the corresponding locking end of the fixture. Accordingly, the hooks of the decorative plate are enabled to be easily engaged with the locking ends of the fixture, respectively, when the decorative plate is pushed against the fixture, thereby enabling the decorative plate to be easily integrated with the fixture, thus resulting in an assembled structure which can be hardly disintegrated once these components are engaged with each other as described above.
It is possible according to the external wall structure of this invention to cover the joint portion between upper and lower siding boards, i.e. a portion of draining member which is exposed to the outside with a desired decorative plate through a simple supplementary work on any occasion as desired, thereby making it possible to easily obtain an external wall surface having an enhanced exterior design.